[Treatment of brain AVMS (TOBAS): A randomized controlled trial and registry]

A combined single-stage procedure to treat brain AVM

Complete resection of brain arteriovenous malformation (AVM) is a surgical challenge, mainly due to risk of intraoperative rupture. The objective of this feasibility study was to analyze complete resection rate at 3 months and clinical outcome at 6 months after treatment of brain AVM by combined single-stage embolization and surgical resection. A retrospective observational study from July 2015 to February 2019 was conducted at the Department of Neurosurgery of Strasbourg University Hospital, France. Decision to treat was taken on the basis of history of AVM rupture, symptomatic AVM, or morphologic risk factors for rupture. Complete resection rate was assessed on postoperative cerebral subtraction angiography at 3 months and clinical outcome at 6 months was evaluated on the modified Rankin Scale (mRS). In the 16 patients treated for symptomatic brain AVM, the rate of complete resection was 75%, resection with residual shunt 18.7%, and incomplete resection with residual nidus 6.3%. Good clinical outcome (mRS=0 or 1) was achieved in 81.3% of patients at 6 months. The transfusion rate was 7.1%. There were procedural complications in 12.5% of patients but no intraoperative ruptures. This combined single-stage procedure allows extensive preoperative embolization of the AVM, facilitating surgical microdissection by identifying the dissection plane and perforating arteries and allowing the operator to work in close contact with the nidus without fear of intraoperative rupture.

Synchronous cerebral arteriovenous malformation and lung adenocarcinoma carcinoma brain metastases: A case study and literature review

INTRODUCTION

While there are numerous published cases of arteriovenous malformations (AVMs) developing in the setting of malignancy, it is extremely rare to find them concurrently associated in the brain.

CLINICAL CASE

This is the case of a 55-year-old male who presented to the emergency department complaining of headaches, memory and visual changes. Neuro-imaging revealed a right temporal parietal AVM and an adjoining hyperenhancing occipitotemporal lobe lesion with concern for a possible evolving stroke. The patient was treated with radiosurgery for the AVM. His symptoms progressed one month later, and repeat imaging suggested interval enlargement of the previously presumed stroke that was intricately associated with the AVM, in addition to two new small enhancing lesions of the left temporal lobe. Microsurgical resection of the temporal lobe mass revealed adenocarcinoma of the lung.

CONCLUSION

This case represents a previously undocumented confluence of cranial AVM that initially masked a non-small cell lung cancer brain metastasis.

Reporting Interim Results Can Show the Feasibility of Practicing Outcome-Based Neurovascular Care Within Randomized Trials: An Opinion

BACKGROUND

Randomized trials of commonly performed surgical interventions are notoriously difficult to conduct. The trial methodology may nevertheless be the best way to offer outcome-based neurovascular care in the presence of uncertainty. One obstacle to promoting such trials is the conventional prohibition of publication and dissemination of interim results as the trial progresses.

METHODS

We review the scientific and statistical reasons against the publication of interim analyses as well as exceptions that can occur when 1 treatment is unexpectedly shown to be harmful or when the results of other trials have convincingly shown the comparative benefits of a new intervention. We also discuss the promotion of difficult surgical trials.

RESULTS

Reasons to support the conventional ban on publication of interim results include control of statistical errors, prevention of invalid conclusions, and dissemination of false claims of equivalence of rival interventions. In the early phases of a trial, usually 1 treatment cannot be shown superior to the other. We believe, contrary to the received view, that a transparent report of the early progress of certain trials can be justified, even when interim results are inconclusive, to promote the recruitment of participating centers and the practice of a novel way to offer neurovascular care in the presence of uncertainty in the best medical interest of patients.

CONCLUSIONS

In our opinion, the early publication of inconclusive interim results may increase awareness of the feasibility of surgical care trials.

The Treatment of Brain AVMs Study (TOBAS): an all-inclusive framework to integrate clinical care and research

OBJECTIVE The management of brain arteriovenous malformations (bAVMs) remains controversial. The Treatment of Brain AVMs Study (TOBAS) was designed to manage patients with bAVMs within a clinical research framework. The objective of this study was to study trial feasibility, recruitment rates, patient allocation to the various management groups, and compliance with treatment allocation. METHODS TOBAS combines two randomized care trials (RCTs) and a registry. Designed to be all-inclusive, the study offers randomized allocation of interventional versus conservative management to patients eligible for both options (first RCT), a second RCT testing the role of preembolization as an adjunct to surgery or radiotherapy, and a registry of patients managed using clinical judgment alone. The primary outcome of the first RCT is death from any cause or disabling stroke (modified Rankin Scale score > 2) at 10 years. A pilot phase was initiated at one center to test study feasibility, record the number and characteristics of patients enrolled in the RCTs, and estimate the frequency of crossovers. RESULTS All patients discussed at the multidisciplinary bAVM committee between June 2014 and June 2016 (n = 107) were recruited into the study; 46 in the randomized trials (23 in the first RCT with 21 unruptured bAVMs, 40 in the second RCT with 17 unruptured bAVMs, and 17 in both RCTs), and 61 patients in the registry. Three patients crossed over from surgery to observation (first RCT). CONCLUSIONS Clinical research was successfully integrated with normal practice using TOBAS. Recruitment rates in a single center are encouraging. Whether the trial will provide meaningful results depends on the recruitment of a sufficient number of participating centers. Clinical trial registration no.: NCT02098252 (clinicaltrials.gov).

Microsurgery for intracranial arteriovenous malformation: Long-term outcomes in 445 patients

BACKGROUND

The management of intracranial arteriovenous malformations(AVMs) poses challenges to the cerebrovascular specialists.

OBJECTIVE

To review the long-term outcomes of intracranial AVMs treated with microsurgical resections.

METHODS

We performed a retrospective review of 445 patients with intracranial AVMs treated in our hospital from January 1st, 2008 to December 31st, 2014. The extracted data included demographic characteristics, clinical presentations, Spetzler-Martin (SM) grades, Supplemented Spetzler-Martin (SM-Supp) Grades, treatment modalities, long-term outcomes, and obliteration rates. Outcome was assessed with a post-operative modified Rankin Scale (mRS) score at the last follow-up visit.

RESULTS

Of the 445 patients treated with microsurgery, 298 (67.0%) patients initially presented with hemorrhage. Based on the SM grading system, the patients were graded as follows: 83(18.6%) Grade I, 156(35.1%) Grade II, 132(29.7%) Grade III, 61(13.7%) Grade IV and 13(2.9%) Grade V. Overall, 344(77.3%) patients had a favorable outcome (mRS score of 0-2). The favorable outcome for Grade I and II were 92.8% and 85.9%, respectively, sharply reducing to 52.5% in patients with Grade IV and 15.4% in patients with Grade V AVMs. 388(87.2%) patients achieved complete obliteration of the AVMs. 63(14.2%) patients experienced recurrent hemorrhage, and the frequency of rehemorrhage was highest in Grade V patients (77.0%), dropping to 3.6% and 3.8% in patients with Grade I and II lesions, respectively. Permanent neurological deficits occurred in 66(14.8%) patients and death in 35(7.9%) patients. There was no difference of AUROC values between SM grading system and SM-supp grading system (0.726 and 0.734, respectively, p = .715).

CONCLUSION

The Spetzler-Martin grading system is a simple and effective method to estimate the risk of surgery and to evaluate the prognosis. Microsurgical resection for AVMs depends on the SM grades, and the morbidity-mortality rate increases with an increasing SM grade.